Transfer box for four-wheel drive vehicles



Juiy 1 2, 194. K. K. PROBST TRANSFER BOX FOR FOUR-WHEEL DRIVE VEHICLES 2 Sheets-Sheet 1 Filed Feb. 7, 1944 v INVENTORV 47 77ZJZ July 12, 1949. K. K. PROBST TRANSFER BOX FOR FOUR-WHEEL DRIVE VEHICLES 2 Sheets-Sheet 2 Filed Feb. 7, 1944 1 N VEN TOR. 77755 z zrz 1 Patented July 12, 1949 2,475,803

UNITED STATES PATENT OFFICE TRANSFER BOX FOR FOUR-WHEEL DRIVE VEHICLES Karl K. Probst, Highland Park, Mich., assignor to Henry J. Kaiser Company, Oakland, Calif., a corporation of Nevada Application February '7, 1944, Serial No. 521,332

Claims.

The invention relates generally to automotive vehicles and it has particular relation to a transfer box through which an engine shaft may be connected to Wheel driving shafts.

having teeth 22 meshing with a lower gear presently to be mentioned. Inwardly beyond the inner ends of the teeth 22, the gear 2| has a separate series of teeth 23 and these are adapted to One object of the invention is to provide an 5 engage teeth 24 formed on the inner periphery of improved type of transfer box which has fewer a clutch ring 25. This clutch ring encircles a parts and is simpler to manufacture and assemble larger portion 21 on the shaft I5 and such lar so as to reduce the cost of manufacture. portion of the shaft has teeth 28 engagin the Another object of the invention is to provide teeth 24 on the clutch ring. If the clutch ring an improved type of transfer box which requires is moved to the left, as seen in Figure 1, the teeth a smaller amount of space and, hence, which bet- 24 will move into engagement with the teeth 23 ter fits designs of smaller power-driven vehicles. on the gear 2| and hence this gear will become Another object of the invention is to provide a drivingly locked to the shaft. simple form of transfer box by meansof which At the opposite side of the larger portion 21, all four wheels of a vehicle may be driven or only the shaft I5 is reduced in diameter, as indicated two of the wheels driven, depending upon which at 3|], and rotatably supports a gear 3| having drive is selected. auxiliary teeth 32 for engagin the teeth 24 on Another object of the invention is to provide the clutch ring. The gear 3| is formed integrally an improved transfer box which obtains a twowith a second shaft 33 projecting outwardly speed drive in a simple and easily selective manthrough an opening 34 in the wall of the cover ner. member H and a grease seal 35 is provided in Other objects of the invention will become apthe Ope and Contacts the hub of a Second parent from the following specification, from the yoke 31 keyed to and fastened to the shaft 33. drawings relating thereto, and from the claims A ball bearing 39 rotatably Supports the Shaft 33 hereinafter set forth. adjacent the gear 3| and both of the ball bearings For a better understanding of the invention, I8 and 39 are located in aligned relation so that reference may be had to the accompanying drawthe axes of both shafts l5 and 33 will coincide. ings forming a part of the specification, wherein: s a in Cooperation With the fitting 0 Figure 1 is a, cross-sectional View illustrating t Smaller Portion 39 0f S t 15 W t n t e a transfer box constructed according to one form gear 3|, holds the two shafts accurately in alignof the invention; ment. Preferablv, small roller bearings, such as Figure 2 is a side-elevational view of the transindicated at are Provided between e inner fer box shown by Figure 1, with certain parts urface of ach ear and the shaft portion upon broken away so as to illustrate structural relawhich t is mounteli It y be mentioned e tions; and that a speedometer connection may be obtained Figure 3 is a cross-sectional view taken sub- With the Shaft 33 by means of a worm 42 prostantially along the line 3-3 of Figure 1. jecting into the cover II and engaging a worm Referring to the figures in the drawings, the Wheel 43 keyed to t e S a transfer box illustrated includes a casing mem- The shaft I6 similarly is mounted inaball bearber H] and a second casing member or cover ing 44 and the outer end of the shaft is secured to which may be connected to the member it] by a universal joint yoke 45. A seal 66 is provided bolts as will be readily understood. The wall of between the opening l3 and the hub of the joint the member Ill opposite the cover I! has openin the same manner as previously stated. Inings I2 and It for allowing shafts 5 and it, wardly of the ball bearing 44, the shaft l6 has a respectively, to project into the casing. A uni- 45 gear 45 thereon which meshes with the teeth 22 versal joint member, such as a universal joint of the gear 2|. Inwardly of the gear 45, the shaft yoke H, is keyed to the outer end of the shaft has a portion provided with teeth 46 and these I5 and inwardly of the hub of the yoke, the shaft teeth engage teeth 41 on a second clutch ring 48. is rotatably mounted in a ball bearing iii. A Beyond the clutch ring, the shaft has a smaller grease seal 20 may be provided in the opening if! 50 portion 50, upon which a gear 5| is rotatably between the outer wall thereof and the hub of the yoke arm for preventing escape of grease from the casing.

Inwardly of the casing, the shaft I5 is provided with a first gear 2| rotatable on the shaft and mounted and this gear next to the clutch ring 48 has teeth 52 adapted to mesh with the teeth 41 on the clutch ring when the latter is shifted to the right. Beyond the gear 5|, the shaft I6 is rotatably mounted in a ball bearing 53 which is located in the casing part I I. The gear 5| meshes with the gear 3| on the upper shaft and when the clutch ring 48 is shifted to the right so that the teeth 47 and 52 engage, gear 5| rotates with shaft i6 and gear 45,

Considering the shaft |5 as the engine shaft or driving shaft, it will be apparent that if the clutch ring 25, sometimes hereinafter referred to as the first clutch ring, is shifted to the right, gear 3| will be driven directly by shaft l5 and hence shaft 33 and universal joint member 3] will be directly driven and at the same rate of speed as the driv, ing shaft l5, A shaft connected to the universal joint member 3! may lead to the rear axle or rea wheels of the vehicle so that the rear wheels will be driven when shaft 33 is turned. If, on the other hand, the first clutch ring 25 is shifted to the left, gear 2| is driven and in turn gear 45 and shaft l6 are driven. If the clutch ring 48 is shifted to the right at the same time that clutch ring 25 is shifted to the left, g ar 5| will also be driven wh n shaf I6 is driven and in turn gear 31 mesh ing with gear 5| will be driven, and finally shaft 33 will be driven also,

Gears 3| and 5| are of the same size and have the same number of teeth so that the speed of shaft I6 is directly transmitted to the shaft 33 in a one-to-one ratio when the clutch 25 is shifted to the left and the clutch ring 48 is shifted to the right. The gear 45 has a different number of teeth as compared to gear 2| and may for s a ce be nearly in the ratio of 2 to 1 so th wh n r 2| is driving gear 45 with clutch ring 25 shifted to the left, the speed of shaft It may be on the order of half of the sp ed of sha t With clutch ring 25 shifted to the right and clutch rin 48 out of engagement with the teeth 5 on gear 5|, shaft 33 alone is driven at the same rate of speed as shaft I5, as mentioned previously.

The shaft It may lead to the front wheels of the vehicle and it might be mentioned here that this shaft can be connected to other shafts leading directly to the wheels so that when shaft I6 is rotated, both front wheels will be rotated. A similar connection may be provided between the rear end of a shaft connected to shaft 33 so that each of the rear wheels will be driven, or, if desired, the universal joint member 31 may be connected to a rearwardly directed transmission shaft leading to a rear axle of the usual type. In any event, re.-

tation of shaft l6 preferably drives the front wheels and rotation of shaft 33 preferably drives the rear wheels. Accordingly, when the clutch member 25 is shifted to the right, the rear wheels will be driven at the same rate of speed as the engine driving shaft I5, or, in other words, a high rate of speed may be obtained, When the clutch ring 25 is shifted to the left and clutch rin 4 t0 the right, both shafts l6 and 33 will be driven at a l w peed and all four wheels of the vehicle will be driven. Hence, the engine may turn all four wheels through a reduction gearing and it follows that much greater power may be obtained. When the vehicle is pulling a large load, it may be desirable to have this reduction earing and to drive all four wheels, while, on the other hand, if the load is not large and speed is desired, a direct drive may be obtained through the shaft 33 leading to the rear wheels while allowing the front wheels to be free from driven connection with the engine.

Referring now in particular to Figures 2 and 3, an arrangement for shifting the clutch ring 25 in either direction includes a fork 60 fitting in a groove 6| in the clutch ring 25. This fork has a hub portion 62 secured to a pin 63 and from this it will be apparent that if the pin is shifted axially, the clutch ring may be shifted axially also. Below the pin 63, a second pin 64 is provided for shifting the clutch ring 48 and this pin has a fork 65 similarly fitting a groove 66 in the clutch ring. For fastening the hub of each fork to its pin, a wedge pin .81 may be provided which fits a similar opening in the hub of the fork and a groove 68 in the pin, and for holding the wedge in position, a stud 69 may be threaded into the opening. The pin 83 is sli-dably supported in openings 78 and H formed in an auxiliary part of the casing member ID while the pin 64 is similarly slidable in openings 12 and 13. A small cover plate 14 secured to the casing part II by bolts provides access to the forks.

The pin 63 may be held in any of three positions so that the clutch ring 25 will be either in neutral position as shown in Figure 1, or so that it will be shifted either to the left or the right. For holding the parts in any one of the three positions, a spring-pressed ball 16 is provided in an opening 1! in the casing and the ball selectively may engage annular grooves 18, 19 and 80 in the pin. This engagement is such that the pin may be shifted past the ball with a given amount of force although normally the ball holds the parts against any loose or accidental shifting. A like ball 8| at the lower end of opening 11 cooperates with grooves 82 and 83 in pin 64 to hold the latter in either of the two positions required for ring 48 to be disengaged from and engaged with teeth 52 on gear 5 I.

For shifting the pin 63, a control lever 85 is pivoted on a stationary pin 86 and the lower end of this control lever has a fork 8'! which straddles a pin 88 fastened to the outer end of the pin. Swinging of the control lever 85 about the pin 86 thus effects axial Shifting of the pin 53 in one direction or the other, A like lever 89 pivoted at 90 is used to move the pin 64,

From the foregoing description it will be apparent that the driver of a vehicle may quickly use one or both driven shafts and that he may connect the rear wheels to the engine shaft by a direct high speed engagement when the clutchring 25 is shifted to the right or drive the rear wheels through a low speed engagement by shifting ring 25 to the left and ring 48 to the right so as to drive through gear 2|, 45, 5| and 3|. The front wheels may be driven at high speed also by shifting ring 48 to the right when ring 25 is shifted to the right and they are driven at low speed when the ring 25 is shifted to the left and ring 48 is shifted to the right. It will be noted that the rear wheels cannot be driven at the lower speed unless the front wheels are also driven at the lower speed and that the front Wheels may or may not be driven at the higher speed along with the rear wheels. It is possible, too, to drive the front wheels alone at low speed by shifting ring 25 to the left while leaving ring 48 in neutral.

Moreover, it will be apparent that the parts are well arranged and that manufacture and assembly is simple. It is to be noted too that the forks 58 and 65 are located at the cover plate l4 so that these parts may be loosened from the pins 63 and 64, and then, after removal of the pins, the forks may be withdrawn through the opening normally closed by the plate.

Although only one form of the invention has been described and illustrated in detail, it will be apparent to those skilled in the art that various modifications may be made without departing from the scope of the appended claims.

What is claimed is:

1. A transfer box comprising a casing, a driving shaft extending into the casing from one side, a driven shaft coaxial to the driving shaft and extending into the casing from the opposite side, a loose gear on the driving shaft, a fixed gear on the driven shaft, a clutch member movable along the driving shaft between the two gears and drivingly connected to said driving shaft, clutch means on the two gears adapted to cooperate with the clutch member so as selectively to connect the gears to the driving shaft depending upon direction of axial movement of the clutch member, a second driven shaft projecting into the casing and parallel to the driving shaft, a gear fixed on the second driven shaft and constantly meshing with the loose gear on the driving shaft, a gear loose on the second driven shaft and being of the same size as the gear fixed on the first driven shaft and constantly meshing therewith, and a clutch member on the second driven shaft and operable independently of the first clutch member for connecting the loose gear thereon to such shaft or disconnecting it therefrom, the loose gear on the driving shaft being smaller than the fixed gear on the second driven shaft.

2. A transfer box of the character described comprising, a drive shaft, a first driven shaft, a gear rotatably mounted on said drive shaft, a gear fixed to said driven shaft, first clutch means associated with said drive shaft for selectively clutching the same to said first driven shaft or for clutching the gear rotatable on said drive shaft thereto, a second driven shaft, a gear fixed on said second driven shaft having meshing engagement with the rotatable gear on said drive shaft, a gear rotatable on said second driven shaft having meshing engagement with the gear fixed to said first driven shaft, and second clutch means associated with said second driven shaft operable independently of said first clutch means for selectively connecting the gear rotatable thereon thereto or disconnecting it therefrom.

3. A transfer box of the character described comprising, a drive shaft, a first driven shaft, a gear rotatably mounted on said drive shaft, a gear fixed to said driven shaft, first clutch means associated with said drive shaft for selectively clutching the same to said first driven shaft or for clutching the gear rotatable on said drive shaft thereto, a second driven shaft, a gear fixed on said second driven shaft having meshing engagement with the rotatable gear on said drive shaft, a gear rotatable on said second driven shaft having meshing engagement with the gear fixed to said first driven shaft, said gear fixed to said first driven shaft and said gear rotatable on said second driven shaft being of the same size, and clutch means associated with said second driven shaft operable independently of said first clutch means for selectively connecting the gear rotatable thereon thereto or disconnecting it therefrom.

4. A transfer box of the character described comprising, a drive shaft, a first driven shaft, a gear rotatably mounted on said drive shaft, a gear fixed to said first driven shaft, first clutch neans associated with said drive shaft for selectively clutching the same to said driven shaft or for clutching the gear rotatable on said drive shaft thereto, a gear fixed on said second driven shaft having meshing engagement with the rotatable gear on said drive shaft, said gear fixed on said second driven shaft being larger than the gear rotatably mounted on said drive shaft, a gear rotatable on said second driven shaft having meshing engagement with the gear fixed to said first driven shaft, said gear rotatable on said second driven shaft and said gear fixed to said first driven shaft being of the same size, and second clutch means associated with said second driven shaft operable independently of said first clutch means for selectively connecting the gear rotatable thereon thereto or disconnecting it therefrom.

5. A transfer box of the character described comprising a drive shaft, a pair of driven shafts, a low speed gear train connectible between said drive shaft and one of said driven shafts, a clutch engageable selectively to establish said low speed gear train or to connect the drive shaft with the other of said driven shafts, a one-to-one speed gear train connectible between said pair of driven shafts, and a clutch engageable to establish said last mentioned gear train, said pair of driven REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 954,531 Mack Apr. 12, 1910 959,878 Page May 31, 1910 2,174,187 Freitag Sept. 26, 1939 2,285,106 Bixby June 2, 1942 

